title: Clinical characteristics of children with hypoparathyroidism due to 22q11.2 microdeletion.
abstract: The phenotypes of chromosomal 22q11.2 microdeletion are quite variable among individuals and hypoparathyroidism (HP) constitutes a definite portion of the clinical spectrum. For the correct diagnosis and pertinent follow up of the HP children due to del22q11.2, we tried to delineate the clinical characteristics of such patients. By employing fluorescence in situ hybridization (FISH) to all the patients diagnosed as HP in our clinic, ten possessed the 22q11.2 microdeletion. Among them, the incidence of cardiac defect (5/10), recurrent infection (1/10) and cleft palate (1/10) was modest. Additionally, seven of them had been diagnosed as HP during the infantile period, when their facial abnormality and intellectual problem had not become evident. Notably, two patients were complicated by Graves disease, while the association of idiopathic thrombocytopenic purpura was also observed in two girls.
  
  
  CONCLUSIONS
  HP due to del22q11.2 may be misdiagnosed as idiopathic, especially in an infant who lacks apparent complications like cardiac anomaly. They should be closely followed up for auto-immune complications.
authors.affiliation: Department of Endocrinology and Metabolism, Kanagawa Children's Medical Centre, Yokohama, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Adachi
authors.forename: K
authors.initials: K
authors.lastname: Tachibana
authors.forename: M
authors.initials: M
authors.lastname: Masuno
authors.forename: Y
authors.initials: Y
authors.lastname: Makita
authors.forename: H
authors.initials: H
authors.lastname: Maesaka
authors.forename: T
authors.initials: T
authors.lastname: Okada
authors.forename: K
authors.initials: K
authors.lastname: Hizukuri
authors.forename: K
authors.initials: K
authors.lastname: Imaizumi
authors.forename: Y
authors.initials: Y
authors.lastname: Kuroki
authors.forename: H
authors.initials: H
authors.lastname: Kurahashi
authors.forename: S
authors.initials: S
authors.lastname: Suwa
mesh_terms: D002648:Child; D002675:Child, Preschool; D002872:Chromosome Deletion; D002892:Chromosomes, Human, Pair 22; D002972:Cleft Palate / Q000175:diagnosis / Q000235:genetics; D004062:DiGeorge Syndrome / Q000175:diagnosis / Q000235:genetics; D003937:Diagnosis, Differential; D005260:Female; D006330:Heart Defects, Congenital / Q000175:diagnosis / Q000235:genetics; D006801:Humans; D007011:Hypoparathyroidism / Q000175:diagnosis / Q000235:genetics*; D017404:In Situ Hybridization, Fluorescence; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D012189:Retrospective Studies